Altretamine - Generic Drug Details

What are the generic sources for altretamine and what is the scope of freedom to operate?

Altretamine is the generic ingredient in one branded drug marketed by Eisai Inc and is included in one NDA. Additional information is available in the individual branded drug profile pages.

Summary for altretamine

US Patents:	0
Tradenames:	1
Applicants:	1
NDAs:	1
Drug Master File Entries:	1
Raw Ingredient (Bulk) Api Vendors:	107
Clinical Trials:	1
DailyMed Link:	altretamine at DailyMed

Recent Clinical Trials for altretamine

Identify potential brand extensions & 505(b)(2) entrants

Sponsor	Phase
Roswell Park Cancer Institute	Phase 1
National Cancer Institute (NCI)	Phase 1

See all altretamine clinical trials

Medical Subject Heading (MeSH) Categories for altretamine

Antineoplastic Agents, Alkylating

Anatomical Therapeutic Chemical (ATC) Classes for altretamine

L01XX	Other antineoplastic agents
L01X	OTHER ANTINEOPLASTIC AGENTS
L01	ANTINEOPLASTIC AGENTS
L	Antineoplastic and immunomodulating agents

US Patents and Regulatory Information for altretamine

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Exclusivity Expiration
Eisai Inc	HEXALEN	altretamine	CAPSULE;ORAL	019926-001	Dec 26, 1990		DISCN	Yes	No

Altretamine Market Dynamics, Patent Landscape, FDA Status, and Financial Trajectory

Last updated: September 6, 2026

Altretamine is an off-patent oral anticancer drug marketed in the United States as Hexalen for persistent or recurrent ovarian cancer after platinum-based or alkylating-agent therapy. Its commercial market is small, mature, and structurally constrained by limited clinical demand, generic competition potential, supply economics, and competition from newer ovarian-cancer treatments. Public filings do not report standalone altretamine revenue, so a reliable product-level revenue forecast cannot be calculated from disclosed financial data.

What is altretamine and how is it used?

Altretamine is an oral alkylating-agent derivative used as single-agent therapy for patients with persistent or recurrent ovarian cancer following treatment with cisplatin and/or other alkylating agents. The product is supplied in 50 mg capsules and is administered orally on a cyclical schedule. The FDA-approved indication is narrow and applies to relapsed disease rather than broad first-line treatment.[1]

Altretamine is not a biologic and does not create biosimilar exposure. Its principal competitors are other systemic treatments for recurrent ovarian cancer, including:

• Pegylated liposomal doxorubicin
• Weekly paclitaxel
• Topotecan
• Bevacizumab-containing regimens
• Mirvetuximab soravtansine for eligible folate-receptor-alpha-positive disease
• PARP inhibitors in selected maintenance or treatment settings
• Platinum rechallenge in patients with platinum-sensitive relapse

The drug’s advantages are oral administration, long clinical history, and relatively simple manufacturing. Its limitations include modest efficacy in a heavily pretreated population, myelosuppression, gastrointestinal toxicity, neurotoxicity, and the availability of more targeted or better-supported alternatives.

What is the FDA regulatory status of altretamine?

Regulatory item	Status
Active ingredient	Altretamine
U.S. brand	Hexalen
Dosage form	50 mg capsule
FDA indication	Persistent or recurrent ovarian cancer after cisplatin and/or alkylating-agent therapy
Initial U.S. approval	1990
Regulatory pathway	New drug application
Biologic status	Not applicable
Pediatric exclusivity	None identified
Orphan-drug exclusivity	Expired, if previously applicable
Current commercial position	Mature, niche oncology product

The FDA approved altretamine in 1990 under NDA 19-832, according to historical FDA labeling and product information.[1] Any original five-year new chemical entity exclusivity expired decades ago. Regulatory exclusivity is therefore not the principal barrier to competition.

The FDA label carries class-related warnings associated with cytotoxic chemotherapy, including hematologic toxicity and neurologic effects. Treatment requires blood-count monitoring and clinical management of nausea, vomiting, and other dose-limiting toxicities.[1]

When does altretamine lose exclusivity?

Altretamine lost meaningful U.S. regulatory exclusivity many years ago. Its original patent and new chemical entity protections are no longer commercially relevant.

The commercial question is therefore not when exclusivity expires. It is whether an abbreviated new drug application, or ANDA, can support a commercially viable product in a low-volume market.

What patents protect altretamine?

No material unexpired U.S. composition-of-matter patent is associated with the original altretamine molecule. Publicly available product information does not identify a current patent estate that would block generic development.

Potential historical or secondary protections could have covered:

• The active ingredient
• Capsule formulations
• Dosing schedules
• Methods of treating ovarian cancer
• Manufacturing processes

Those protections would have expired or become commercially immaterial given the drug’s 1990 approval date. No significant current formulation patent or method-of-use patent is generally recognized as a barrier to U.S. entry.

Patent category	Current commercial significance
Compound patent	None apparent
Formulation patent	No material barrier identified
Method-of-use patent	No material barrier identified
Manufacturing patent	Possible process know-how, but not a recognized exclusivity barrier
Patent-term extension	Not commercially relevant
Regulatory exclusivity	Expired

What is the Orange Book status of altretamine?

The Orange Book historically listed Hexalen as the reference product for altretamine capsules. The practical significance of any listing is limited because the original product is decades beyond its exclusivity period.[2]

An Orange Book listing does not itself create a continuing market monopoly. It identifies approved products and, where applicable, patent information relevant to ANDA certification. For altretamine, generic developers would principally face technical, commercial, and supply considerations rather than a significant patent challenge.

Because Orange Book entries and marketing status can change, the relevant business issue is whether the reference product and any generic products are currently listed as active, discontinued, or available for commercial distribution. FDA’s Orange Book and Drugs@FDA databases are the controlling sources for current product status.[2,3]

How many patents cover altretamine?

No significant active U.S. patent estate is publicly associated with altretamine as a product. The molecule’s patent position is effectively exhausted.

This creates a contrast with newer ovarian-cancer products:

Product	Primary protection profile	Competitive barrier
Altretamine	Expired molecule and regulatory protections	Low patent barrier
Mirvetuximab soravtansine	Biologic and antibody-drug conjugate patents, regulatory exclusivity	High technical and regulatory barrier
Olaparib	Small-molecule and method-of-use protections, many expired or expiring claims	Moderate, depending on indication
Niraparib	Small-molecule and method-of-use protections	Moderate
Pegylated liposomal doxorubicin	Mature product with formulation and manufacturing complexity	Moderate technical barrier

Altretamine’s lack of patent protection increases the theoretical risk of generic entry. It does not guarantee entry because the addressable market is small and oncology manufacturing economics may be unattractive.

Which companies are challenging altretamine?

No prominent recent Paragraph IV litigation or settlement involving altretamine is widely reported in the principal public patent and FDA sources. The absence of visible litigation is consistent with a low-value, mature product whose expected sales may not justify substantial patent litigation.

Potential generic competition would most likely arise through an ANDA rather than a 505(b)(2) application. An ANDA applicant would need to demonstrate bioequivalence to the listed reference drug and meet manufacturing, quality, labeling, and supply requirements.

The commercial threat is therefore better characterized as latent generic risk rather than active patent litigation.

What generic launch risks exist?

A generic entrant would face several constraints:

1. Small patient population and limited prescription volume.
2. Low inventory turnover and the need to maintain oncology-grade supply reliability.
3. Potentially limited reimbursement upside after discounts and rebates.
4. Reference-product availability requirements for bioequivalence development.
5. Competition from established therapies with stronger guideline positioning.
6. Manufacturing economics that may not support multiple suppliers.

These factors can preserve a single-source or limited-source market even after patent expiry. They can also produce abrupt price increases if a manufacturer exits or experiences a shortage.

What formulations are protected by altretamine patents?

The commercial product is an oral 50 mg capsule. No active formulation patent is generally recognized as protecting a differentiated extended-release, liquid, injectable, or abuse-deterrent version of altretamine.

The absence of alternative dosage forms limits lifecycle-management opportunities. A manufacturer cannot easily extend the product’s market through a new delivery platform comparable to liposomal delivery, long-acting injection, or targeted antibody-drug conjugation.

Manufacturing know-how may still matter. Cytotoxic handling, content uniformity, capsule filling, stability, packaging, and quality-control procedures can create operational barriers even when patent protection has expired. Those barriers are commercial and technical rather than exclusivity-based.

How strong is the altretamine patent estate?

The patent estate is weak from a blocking-rights perspective and has little value as a licensing asset.

Strength factor	Assessment
Composition-of-matter protection	Exhausted
Regulatory exclusivity	Exhausted
Formulation differentiation	Limited
Method-of-use protection	Limited
Manufacturing complexity	Moderate
Generic litigation leverage	Low
Licensing value	Low unless linked to supply or regional rights

Altretamine may still have value in a portfolio of mature oncology products, particularly for a company with an established hospital, specialty-pharmacy, or cancer-care distribution network. Its value would come from cash generation, portfolio completeness, and supply relationships rather than patent exclusivity.

What is the competitive landscape for altretamine?

Altretamine occupies a late-line segment of ovarian-cancer treatment. Its competitive position has weakened as treatment has become more biomarker-driven and as clinicians have gained access to targeted therapies.

The market is shaped by four factors:

Disease-line positioning

Altretamine is not a broad first-line ovarian-cancer product. Its label focuses on persistent or recurrent disease after prior chemotherapy. That restricts the eligible population.

Clinical substitution

Physicians can choose among several cytotoxic and targeted options. Selection depends on platinum sensitivity, prior treatment, biomarker status, toxicity, performance status, access, and payer policy.

Oral administration

Oral delivery can reduce infusion-center use and may appeal to some patients. It also shifts adherence, monitoring, and medication-management responsibilities to the patient and oncology practice.

Toxicity and evidence base

Altretamine’s long history supports familiarity, but newer products may offer stronger evidence in defined molecular or clinical subgroups. That weakens the drug’s ability to gain share without a price or access advantage.

What is the financial trajectory of altretamine?

No major manufacturer publicly discloses standalone altretamine revenue, unit volume, gross margin, or regional sales. The product is generally included within broader branded, generic, or specialty-pharmaceutical reporting.

The most defensible financial characterization is:

• Revenue base: small relative to modern oncology products
• Growth profile: mature to declining absent a supply disruption or price event
• Margin profile: potentially attractive at limited scale, but sensitive to manufacturing and distribution costs
• Volume outlook: constrained by narrow labeling and treatment substitution
• Pricing risk: elevated because the molecule is off-patent
• Generic risk: structurally high, but moderated by low market size
• Revenue durability: dependent on continued product availability and limited competitive entry

A simple financial model should use prescription volume, average net price, treatment duration, payer mix, and manufacturer share. Public information is insufficient to support a reliable absolute revenue estimate.

What could increase altretamine revenue?

Revenue could rise through:

• Supply disruption affecting competing therapies
• Price increases in a single-source or limited-source market
• Expanded distribution through oncology specialty pharmacies
• Increased use in resource-constrained treatment settings
• Manufacturer acquisition of a broader mature-oncology portfolio
• Temporary shortages of alternative cytotoxic agents

These are event-driven opportunities rather than durable growth drivers.

What could reduce altretamine revenue?

The principal downside factors are:

• Generic entry
• Manufacturer discontinuation
• Persistent oncology-drug shortages
• Physician migration to targeted treatments
• Reimbursement pressure
• Declining use of older cytotoxic therapy
• Clinical preference for better-tolerated or biomarker-selected drugs

What patent litigation affects altretamine?

No material current patent litigation is broadly associated with altretamine. The product’s litigation exposure is low because there is no meaningful active patent estate to enforce.

The more relevant legal risks are commercial:

• Contract disputes involving supply and distribution
• Product-liability claims
• Manufacturing-quality enforcement
• Labeling and pharmacovigilance issues
• Antitrust or price-related scrutiny if market supply becomes concentrated

Patent litigation would become relevant only if a company developed a new formulation, delivery system, or clinically differentiated method of use and obtained enforceable claims.

What licensing deals involve altretamine?

Altretamine has limited licensing attractiveness because its original molecule is off-patent and its market is narrow. A licensing transaction would more likely concern:

• Regional commercialization rights
• Supply agreements
• Portfolio acquisitions
• Distribution rights
• Manufacturing transfer
• Hospital or specialty-pharmacy contracts

No major recent global licensing transaction is generally associated with altretamine. Its likely transaction value is tied to inventory, regulatory rights, manufacturing capability, and distribution infrastructure rather than future patent royalties.

How does altretamine compare with newer ovarian-cancer drugs?

Attribute	Altretamine	Newer targeted ovarian-cancer drugs
Administration	Oral capsule	Oral, intravenous, or antibody-drug conjugate
Target population	Broad but late-line, heavily pretreated patients	Often biomarker- or line-specific
Patent position	Essentially exhausted	Often active or recently expired
Regulatory exclusivity	Expired	May remain active
Clinical differentiation	Limited	Often tied to molecular selection
Generic or biosimilar risk	Generic risk	Patent, biologic, or complex-product risk
Revenue potential	Low and mature	Higher for successful targeted products
Manufacturing barrier	Conventional cytotoxic manufacturing	Often materially higher

Biosimilar risk does not apply directly to altretamine. The relevant competitive threat is generic substitution and therapeutic substitution.

What is the generic launch scenario for altretamine?

The most likely scenarios are:

Scenario	Market effect
No new entrant	Continued niche sales, potentially with price volatility
One generic entrant	Lower price and reduced branded share
Multiple generic entrants	Significant price erosion and possible supply consolidation
Brand withdrawal	Generic or imported supply becomes central
Supply disruption	Temporary price increase and substitution to other cytotoxic agents

A generic launch would probably reduce the branded product’s share quickly if the generic is listed as therapeutically equivalent and available through major wholesalers. The absolute market impact would remain limited because the underlying patient population is small.

What is the geographic coverage of altretamine?

The most commercially relevant market is the United States because Hexalen received U.S. FDA approval and has an established U.S. labeling history. Availability in other countries varies by national registration, reimbursement, local manufacturing, and oncology-treatment guidelines.

Geographic expansion is difficult to justify without:

• A registered local product
• Reliable cytotoxic manufacturing
• Reimbursement coverage
• A distribution partner
• Sufficient patient volume

The product’s low innovation profile limits its attractiveness for new-market expansion.

Key Takeaways

• Altretamine is a mature oral oncology drug approved in the United States in 1990.
• Its FDA indication is persistent or recurrent ovarian cancer after prior cisplatin and/or alkylating-agent therapy.
• Original patent and regulatory exclusivity protections have expired.
• No material active U.S. formulation or method-of-use patent estate is broadly recognized.
• No prominent current Paragraph IV litigation or settlement is associated with the product.
• The drug faces both generic-entry risk and therapeutic substitution from newer ovarian-cancer treatments.
• Public companies do not generally disclose standalone altretamine revenue.
• Its financial profile is likely low-volume, mature, and sensitive to supply concentration.
• Manufacturing and distribution economics, rather than patents, are the main barriers to competition.
• Biosimilar competition does not apply because altretamine is a small-molecule drug.

FAQs

Is altretamine still FDA approved?

Yes. Altretamine remains associated with the FDA-approved Hexalen labeling for persistent or recurrent ovarian cancer after prior chemotherapy. Current commercial availability should be checked through FDA product databases and current labeling records.[1-3]

Is altretamine a generic drug?

Altretamine is an off-patent small-molecule drug. Whether a currently marketed product is branded, authorized generic, or a separately approved generic depends on active FDA listings and commercial distribution.

Can altretamine be used for breast or lung cancer?

Its FDA-approved indication is ovarian cancer. Use in other cancers would be off-label and would depend on clinical judgment and supporting evidence.

Does altretamine have orphan-drug exclusivity?

Any original orphan-drug exclusivity associated with the product would have expired decades ago. It does not provide a current commercial barrier.

Is altretamine a high-value licensing opportunity?

Usually no. The principal value is in mature-product cash flow, supply rights, distribution, or portfolio fit. Patent royalties and exclusivity-driven valuation are not strong sources of value.

References

1. U.S. Food and Drug Administration. (1990). Hexalen (altretamine) capsules prescribing information. FDA.

2. U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: Orange Book. FDA.

3. U.S. Food and Drug Administration. (2024). Drugs@FDA: FDA-approved drugs database. FDA.

4. National Cancer Institute. (2024). Ovarian, fallopian tube, and primary peritoneal cancer treatment. National Cancer Institute.

5. National Comprehensive Cancer Network. (2024). NCCN clinical practice guidelines in oncology: Ovarian cancer, including fallopian tube cancer and primary peritoneal cancer. NCCN.